In a randomized controlled trial on the diet of patients with irritable bowel syndrome, serum proinflammatory IL-6 and IL-8 levels, and faecal abundance of actinomycetes, bifidobacteria, and E. faecalis were significantly lower in patients on the low-FODMAP diet (Hustoft et al., 2017). The gene discussed is CXCL8; the disease is irritable bowel syndrome.